• Share Your Car Experience
      Share Your Car Experience
    • Huge Range of Ford Parts
      Huge Range of Ford Parts
    • Savings Up to 15% Off For Members
      Savings Up to 15% Off For Members
    • Join Premium & Save
      Join Premium & Save
    • 1000's Of Fords For Sale
      1000's Of Fords For Sale
    • Get Your Club gear
      Get Your Club gear


540itouring

Low Coolant Warning Project questions

Recommended Posts

I have ordered a coolant level switch and will fit this in the side of the coolant tank and has a seal and nut to make a good seal on the tank and hole will be 16.5mm . I was just going to wire this up to a LED and get this to light if the level switch detects coolant level drop but was then thinking does this dash have a UNUSED coolant level light ? Does any one know How the High temp warning light is triggered ? I expect the ECU lights this by monitoring the coolant temp sensor resistance , NTC ?      If so thinking of a circuit to alter this resistance to enable the dash high temp light to light of flash when low coolant level detected from my new switch . Does any one know the resistance required by the ecu in order to light the red high temp light . I like the idea of a flashing temp light and wondered what the normal high temp light does when the engine is cooked . Does this red light stay on or flash ?   please help as it will be a great add on for all ecoboost engine cars

 

 

Share this post


Link to post
Share on other sites
 

You'd have to add a time delay or mount it extremely low down otherwise any bumps or sloshing would upset the coolant level 

Share this post


Link to post
Share on other sites

Bearing in mind that you hope never to witness this alarm I'd suggest keeping things as simple as possible. A buzzer would fit the bill; can be easily hidden out of sight, produces a warning that would get instant attention and avoids the risk of inadvertently upsetting any of the existing electronics. 

Share this post


Link to post
Share on other sites

I purchased a preprepared one with a buzzer from eBay but haven't installed it yet as it requires drilling into the plastic coolant tank. Not sure if that's a good idea. 

Share this post


Link to post
Share on other sites

its a good idea to install your own coolant level monitor but a bit risky to use the same dash warning light for both temp & level 

i wouldnt want to crash the control module from having it receive 2 sets of resistance values from different types of sensor in order to trigger the same warning light

you have a bigger chance of success by using a small dash mounted led in my op.

Share this post


Link to post
Share on other sites

This is the level sensor I have ordered and works with temps -10 to +120C   so no problem with the range. I will remove the tank and drill with care and may just file the hole to the required size . I will then refit the tank and then think about what warning system is best to warn the driver of coolant loss. This type of sensor will not give false alarm as long as fitted below the water level and is fitted to the inside of the tank with sealing washer and nut on the outside of the tank. The reed switch is only designed to switch a signal or very low current so will need to switch a transistor or relay in order to control higher current.

 

Share this post


Link to post
Share on other sites

I can't remember the exact form/layout of the coolant tank but do you think there'll be sufficient 'drop' inside it to allow the switch to function? To put it another way; even with a fully depleted tank will the float fall far enough to trigger?

Incidentally the reed switch will cope with pretty much anything you might reasonably consider attaching to it e.g. LED, buzzer etc.

Share this post


Link to post
Share on other sites
13 minutes ago, MJNewton said:

I can't remember the exact form/layout of the coolant tank but do you think there'll be sufficient 'drop' inside it to allow the switch to function? To put it another way; even with a fully depleted tank will the float fall far enough to trigger

I will test with a meter to confirm operation before fitting but I am sure this will work with the space and think this will trigger of approx.  30 deg  float drop should be all it needs to break the circuit.

 

 

 

 

.

 

Share this post


Link to post
Share on other sites

looking into a warning indication for low level. Thinking of getting a second hand cluster to dismantle and see what options I have. I may look at adding a yellow led for the high temp light so I can add a extra input to the red temp  symbol . option 2 it would be easy to trip the low brake warning light by making it flash. Option 3 would be to trigger the chimes ?

 

Does any one know if the dash has a unused coolant level light ?  I expect we will not be that lucky

 

 

 

Share this post


Link to post
Share on other sites

I have had many years working with electronics and always like to fit upgrades to the best possible standard and most of all work well and always must look factory fit.

 

My sensor will come today so will do some tests to confirm it will work ok in the space available and then fit this to the tank. I am just looking at the circuits so I can see all options available first but don't think this will be long before its done.

Share this post


Link to post
Share on other sites
4 hours ago, 540itouring said:

I have had many years working with electronics and always like to fit upgrades to the best possible standard [...]

You will be very aware of the principle and benefits of KISS hence my surprise at you trying to seek such a tightly integrated solution, not least for an event you should expect (or at least hope!) never to actually see occurring.

Quote

and most of all work well and always must look factory fit.

Fully agree on that point. Moreover, however, I would say you want something that doesn't 'look' at all e.g. the use of a buzzer secreted behind the dash that is completely independent of anything but the monitoring circuit itself. This ought to maximise reliability, maximise attention seeking (an audible alarm could attract your attention sooner than a visible indicator and in the case of coolant loss every second will count), minimise cost and minimise effort. As an electronics engineer myself I'm all for smart and clever solutions - even for no other reason than 'because you can' - but selecting them over other, more basic, options that might offer greater benefits is usually done at your peril.

On a completely different note did you consider a non-contact fluid sensor so as to avoid hacking the reservoir? The last thing you will want is your detection method actually being the cause of the thing you are trying to detect! ;-)

Share this post


Link to post
Share on other sites
6 hours ago, MJNewton said:

.

On a completely different note did you consider a non-contact fluid sensor so as to avoid hacking the reservoir? The last thing you will want is your detection method actually being the cause of the thing you are trying to detect! ;-)

This ^^^^ 

Share this post


Link to post
Share on other sites
7 hours ago, MJNewton said:

 

On a completely different note did you consider a non-contact fluid sensor so as to avoid hacking the reservoir? The last thing you will want is your detection method actually being the cause of the thing you are trying to detect! ;-)

 

I looked into other sensors and all I found was a ebay contactless sensor for under £5 inc  postage  from china . I can not see this being a reliable sensor . I am sure that when I cut a smooth hole for this sensor it will seal fine and strengthen around by the nuts on the sensor.

 

My new sensor did not come today so hope it comes tomorrow.

Share this post


Link to post
Share on other sites

I have done some more work on this and now after testing a ebay contactless sensor they seam just the job. I have now fixed a sensor to the outside of the coolant tank with jb weld and now ordered a reed relay. I have tested the car sensors and I am now going to use the brake fluid level sensor as this is almost just what is required. When I trip the system with ignition on the brake warning symbol lights , front display monitor dispays LOW BRAKE FLUID SERVICE NOW and also the dast emits the warning CHIMES.  This will give a perfect indication that the coolant is low so will stop the car much sooner than a high temp warning light in AIR due to low coolant.

 

I am now working on a electronic interface to drive the relay from the output of the new coolant level sensor and switch in a resistor to trip the warning system. The low brake warning will still function as normal.

ecoboost sensor.jpg

Share this post


Link to post
Share on other sites
19 hours ago, 540itouring said:

I have done some more work on this and now after testing a ebay contactless sensor they seam just the job. I have now fixed a sensor to the outside of the coolant tank with jb weld and now ordered a reed relay. I have tested the car sensors and I am now going to use the brake fluid level sensor as this is almost just what is required. When I trip the system with ignition on the brake warning symbol lights , front display monitor dispays LOW BRAKE FLUID SERVICE NOW and also the dast emits the warning CHIMES.  This will give a perfect indication that the coolant is low so will stop the car much sooner than a high temp warning light in AIR due to low coolant.

 

I am now working on a electronic interface to drive the relay from the output of the new coolant level sensor and switch in a resistor to trip the warning system. The low brake warning will still function as normal.

 

This looks like just the thing. I've resisted installing the setup I have as I'm not keen to cut into the coolant tank. Can I ask you which sensor you chose?  I have only been able to find those that trigger on full rather than empty. 

Share this post


Link to post
Share on other sites

this is the sensor that I am going to use. This sensor also gives a supply voltage output when the water is normal . This will not be a problem as I will design a inverter circuit with transistors and a reed relay to give 12 volt out when no water detected. The relay will then switch and put a resistor in parallel with the low brake warning sensor. This circuit will keep the wiring simple and all local to the coolant tank and just need to find 12 volt supply the same side of the engine bay if possible. When I get the relay I will make a circuit to do the switching.

http://www.ebay.co.uk/itm/Switch-Water-Contactless-Liquid-Level-Sensor-Interface-Type-Sensors-Detectors/142197530419?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

 

Share this post


Link to post
Share on other sites

Not yet as my mum passed away a few weeks ago but hope to have a update very soon. I just need to wire it all up which should be the easy part.

Share this post


Link to post
Share on other sites

I have now run three wires across the back of the engine loom for two power cables and one data cable. These are to power ST Cat 1 alarm conversion with interior scan in roof light and the other power cable is for my low coolant warning system. I will try if I have time tomorrow afternoon to wire the alarm sounder and then the low coolant sensor and reed relay. I will then just need to re config the body computer to change alarm system to Cat 1 (all ready set up interior scanner) and test the alarm and low coolant warning. Today took me a long time running the cables as I wanted to put these inside to standard loom as much as possible and then had to run a data wire for the alarm sounder to the passenger footwell..

tomorrow should be easy apart from making this all look neat. when I get this done I will try to make a video of the coolant warning working by lifting the coolant tank and tilting it to trip the low level. 

No programming or data wires are needed for the coolant warning as this was only for the cat 1 alarm change.

Share this post


Link to post
Share on other sites

Update

I wired the coolant sensor and relay including resistor and connected the power to a new fuse. Started car and switched to radio display and all works as before. I then with engine running removed coolant tank from fixings and tilted tank so coolant was below the sensor. After about 10 seconds the gong sounds about three times and the monitor then displays BRAKE FLUID LOW   . I this refitted the coolant tank while engine still running and the low brake fluid warning is turned off waiting for a repeat low level signal from the sensor so all works perfect

 

I then reprogrammed the body computer and wired up the data wire and new power fuse for my CAT 1 Alarm conversion and again all works perfect and can now open boot with alarm set and close without tripping the interior sensor.

I will try to take some pics to show you the warning and install later.

I can sleep now as all possible extras are fitted and working and I know my ecoboost will not melt !

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now